Wahoo! my first sticky! Made some edits, need comments and corrections

This is even better than when I became a 'burning chunk'.

I've added wiring schematics to the initial post in my pressurized storage sticky.

As far as I can tell, it's a closed thread, so there's no vehicle to collect comments, corrections, and improvements. In the very likely case that someone finds something to add, perhaps a response to this thread will serve. I can still edit my post, so I'll update / improve as needed.

You have "woul" for would in there somewhere, other then that very educational. ~Thank you!

My only comment is that you can get a new aquastat like the Honeywell L6006A1145 for around $20 on Ebay if you're reasonably patient.

I don't want the sticky thing to get out of control, but I think we can avoid that by eventually combining this kind of excellent thread with others on similar topics into one sticky. So, the sticky "Storage Considerations and Options" would consist of a brief discussion/explanation, followed by links to this piece on pressurized storage and another one on non-pressurized storage. Ditto for parallel vs serial boiler setups and hotrod's piece on primary/secondary piping schemes. That one could be called "Piping Possibilities." Ideally, I'd like to see about half a dozen stickies covering broad categories (our FAQs), linking to threads on specific facets of the main topic.

Anyway, thanks to nofo for blazing the way.

Good call on the eBay reference. I'm conflicted about mentioning sources to be helpful vs. being scrupulously non-commercial.

Perhaps what we need at some point is a 'Resource Room' that contains only stickies. There was some discussion in the past about creating a meta-thread that pointed to useful threads. Anything that makes it easier for folks to find the threads with meat in them would help to reduce the amount of re-explaining that happens otherwise.

I'm not holding my breath about getting credit from anyone, but that's not why I'm in this game anyway. I just hope that we can move this technology forward in a way that benefits as many people as possible.

I hope a few other hard-core experts review this and catch any mistakes I might have made. I'd really hate for someone to follow this as if it were a recipe and then run into problems.

nofo,

The new sticky is a wonderful resource. Thanks. Minor detail, but would there be a way to stack the image attachments one on top of the other so that we don’t have to scroll side to side to read the text above them?

Ron

I think that's a question for Web. I would have done the additional images as replies to the original post, but he locked it to keep it as a pristine thread. That's a wonderful thing in most ways, but it limits my options. Note - it's fine on my 3200 pixel wide screen ;-)

Excellent work nofo.

By zone valve limit switches I assume you mean end switches?

The only part I am having trouble with... Lets say there is a call for heat on one bb zone. Wood boiler and circ is running, storage at or below 180F. as I understand it the system circ will also be running? Doesn't this put the boiler circ and system circ in series and create some excessive velocity issue? What determines how much flows down into storage, and how much goes to the zone?

Would a motorized 3 way zone valve be a good application so either the boiler feeds directly, or the storage does. Although one zone may not be enough load for the boiler under some conditions. It would be interesting to install some flow gauges to see what happens under different load conditions. Strap on thermostats would give you some idea, but flow sensitive measurement would be more accurate.

Bottom line... if it works, heats, is noise free, and consumes the wood you are comnfortable with, bingo. Thanks again for sharing this work.

hr

Nice diagram and explanation. I was wondering if the flow could be a problem through the storage tank if a zone(s) is calling for heat (as you noted) by the differences in flow between the pumps. It made me think that adding a hydraulic separator and having the tank with its own pump would eliminate any flow conflicts as master of sparks mentioned. For reference only ( I do not use this or sell them):
http://www.caleffi.us/caleffi/en_US...gazine_detail_0000054/type/magazine/index.sdo

Once again the challenge to any good project is keeping it simple while efficient.

The only other problem for me is making the retrofit from my current traditional baseboard system to the method shown. It would be a lot of piping changes. I have some kind of hybrid approach in the works and hope to have the drawing done soon.

Mike

Thanks. Yes, I think they're called 'end switches' in that application. In my world, the same physical device is usually called a limit switch. In any event, it's the switch whose contacts close when the zone valve is open.

It does put them in series, and would result in a bit more flow through the loop than you would get with a single circ. As far as the split between the zone and storage, the system circ will ensure that you have adequate flow through the zones. If the boiler circ puts out a higher flow rate than that, the difference goes through storage. If you're dealing with high flow rate pumps, it would be important to have a large diameter connection to the top of the storage. You could actually have two adjacent connections to the top of the storage, so that the boiler is always feeding the top of storage and the system circ is always drawing from th top of storage. In that way, it would eliminate the 'pumps in series' phenomenon. I did draw it with tees oriented to help hydraulically separate the pumps.

I also expect that the way it's drawn, there will be very little pressure drop in the boiler - storage loop, and especially almost no pressure drop from the storage top to the storage bottom. If that's the case, then the system circ would not be able to tell whether the boiler circ is running, and vice versa - they would not affect each other.

Thanks for the analysis. My sense is that additional complexity and expense such as a 3 way valve might be necessary in larger and more complex installations, but would not be needed in systems on the scale that I've drawn. Does that seem right to you, given my thoughts above on hydraulics?

See my thoughts above - make sense to you?

I tried to come up with an approach that would be easy as a retrofit. Sorry if it's not so simple in your case :-(

nofossil, Thanks again for your excellent post "Simplest Pressurized Storage Solution"
I plan on going with a 500 gallon propane pressurized tank. I now have my TarmSolo40 piped parallel to my oil boiler without storage as per Tarm instructions. I'd like to utilize my oil boiler to feed my zones and SuperStor DHW. Not bypass it as I believe you do in your drawings. I'm thinking of going from the Tarm, feeding either the storage tank or oil boiler with a 3-way zone valve, oil boiler will be primary if its aquastat calls for heat. Then from the storage tank feeding the oil boiler with an additional circulator. Do you have any thoughts on this?
Total of three circulators, one 3-way zone valve.
I wish I had a pipe drawing program.

I'm looking at a similar approach and have a boiler inbound and a 500 gallon tank on hand.

All seems perfect until I realized that the leftover propane stink is something I don't want contaminating
my house/heating system... that stuff is as persistent as it is nasty.. .. Either isolate the tank
via heat exchanger or a new tank.. Unless I can absolutely get that stuff out of the tank to a like new
condition I'm very leery of hooking up a used propane tank to my heating system..Imagine it's middle of
winter and something fails and releases this into your house...whew...what a mess...it never goes away...OMG

MM

Can the propane stink (mercaptan) be successfully flushed? I heard chlorine bleach, hydrogen peroxide. What works the best?
I'm gonna give this place that sells refurbished tanks a call. They want 950.00 for a 500 gallon propane tank. No delivery. That's top dollar. I'll see if they can throw in a flush.

In the posted schematic, the oil boiler will feed the zones and SuperStor. Nothing is 'bypassed'. The control configuration that I suggest will have the DHW and zones supplied by the wood boiler if it's hot, by the tank next, and by the oil only if the wood and tank are cold. The oil never heats the storage tank.

The Tarm instructions show a series installation, but call it parallel. I think they do it that way so that if you have a hot water coil in your oil boiler you will get hot water. Since you have a Superstor, there's no reason that I can see to circulate hot water through your oil boiler if it's not operating.

High flow 3 way valves are expensive, I think. Part of my goal was to reduce the cost and complexity to a minimum so that folks with straightforward requirements aren't overwhelmed with the magnitude of the project.

However, there are plenty of cases where additional cost and complexity are appropriate. There's another sticky that shows a very elegant promary/secondary system, for instance.

"Nothing is ‘bypassed’. "The control configuration that I suggest will have the DHW and zones supplied by the wood boiler "

In my current piping configuration to supply the zones by either the wood boiler or storage, according to your drawing, I would have to by-pass the oil boiler. I know its probably more efficient to do so but I would have to do quite a bit of existing piping alteration.

I see what you mean. I've drawn a parallel configuration in which the oil is 'bypassed' when heating with wood and vice versa. I don't think of it as bypassing since there's no control action taken to route flow around the inactive unit. I suppose I should talk to the Tarm folks and see if there's any other reasons for their suggested plumbing configuration. You're not the first to set it up that way, and I've never understood the reasons for it other than the DHW coil issue that I mentioned earlier.

nofossil, I'd like your opinion to my previous post:

I’m thinking of going from the Tarm, feeding either the storage tank or oil boiler with a 3-way zone valve, oil boiler will be primary if its aquastat calls for heat. Then from the storage tank feeding the oil boiler with an additional circulator. Do you have any thoughts on this?
Total of three circulators, one 3-way zone valve.
I wish I had a pipe drawing program.

I use Visio for pipe drawing, although I've used a pencil, paper plate, and digital camera before ;-)

I haven't quite constructed a diagram in my mind from your description. Sounds like you'd be pumping through your oil boiler regardless of the heat source. I assume that there would be losses from doing that, though I have no hard data on how much. Do you have a way in this setup to pump from the top of storage when you're using storage for heat? Does the three-way valve allow intermediate settings so that a portion of the flow can go each way? As some zones are satisfied, you'd like to start charging storage with any leftover heat.

"Sounds like you’d be pumping through your oil boiler regardless of the heat source. "
Thats exactly what I plan on doing. Make my existing oil boiler the heart of my heating system, but leave out the oil.

"Do you have a way in this setup to pump from the top of storage when you’re using storage for heat? "
I'd imagine I'll just vary the size of the dip-tube in the propane tank.

"Does the three-way valve allow intermediate settings so that a portion of the flow can go each way? "
No, the 3-way would be controlled by an aquastat in the Oil boiler. When the oil boiler calls for heat, all the wood boiler heat goes to the oil boiler. When the oil boiler is satisfied, all the wood boiler heat goes to storage.

Basically 3 loops in this system. Three circulators. If you don't see anything drastically wrong with this I feel its a very simple way to utilize what I have easily. I guarantee you I will always look to revise and improve this.

Sorry - gotta have either a picture or a more detailed description. I don't understand everything yet. Here's what I think you have:

- Oil boiler with circ connected to inlet
- Wood boiler with circ connected to inlet
- Storage with circ connected somewhere?
- 3-way valve
- Heat zones

- Outlet of wood is connected to inlet of 3-way
- Outlet A of 3-way is connected to inlet of oil boiler/circ
- Outlet B is connected to top of storage
- Outlet of oil boiler/circ is connected to zone supplies
- inlet of oil boiler/circ is connected to zone returns
- Inlet of wood boiler/circ is also connected to zone returns?
- Storage circ draws from bottom of storage and pumps to oil boiler/circ inlet?

I don't have a copy of Tarm's schematic. With what you've described, I don't understand how flow happens through storage charging vs. discharging.I also don't understand where the wodd boiler inlet is connected. Wish I could be of more help.

nofossil, I sent a quick sketch to wkuhns@nofossil.org.
Don't laugh.